1. Field
The invention pertains to building construction in which mechanical clips are utilized to fasten composite insulating panels to one another, edge-face to edge-face, and to supporting building structure.
2. State of the Art
The advantages of foamed plastic insulation are well known. It has been common practice to apply sheets of foamed plastic insulation, usually foamed polyurethane or polystyrene, to concrete, steel, and masonry walls, ceilings, and roofs by means of an adhesive and/or mechanical fasteners. To finish the wall and provide a protective shield for the foamed plastic insulation, gypsum wallboard panels have been adhesively secured to exposed faces of the foamed plastic sheets. Furring strips, studs, or undersized studs, have also been attached to the concrete, steel, or masonry walls, with the foamed plastic sheets and wallboard panels nailed and/or glued to the furring strips or studs.
U.S. Pat. No. 3,401,494 discloses a wall construction in which sheets of foamed plastic insulation are secured to masonry or concrete walls using elongate, channel-shaped fasteners that are pressed into the sheet of insulation at spaced intervals, so that web portions of the respective fasteners are flush with the exposed faces of the sheets. Nails or power-driven pins are passed through the fasteners and into the wall. Gypsum wallboard panels are then positioned over the respective sheets of insulation, and screws are driven through the panels and into the web of the fasteners.
U.S. Pat. No. 3,510,391 discloses a composite insulation board formed by a foamed plastic sheet laminated directly to a perlite insulation board. The advantage of such a one-piece panel is that it can be applied to a supporting structure in one step. However, if nails are used to secure the panel to the structure, some deformation of the foamed insulation portion of the panel occurs, which decreases the effectiveness of the foamed insulation in the vicinity of the nails. In addition, the nails that penetrate the insulation material readily transmit heat through the composite panel, thereby further decreasing its insulating properties.
There is no provision in either of the systems described in U.S. Pat. Nos. 3,401,494 and 3,510,391 for providing flush surface alignment between adjoining panels, or for providing an air space between the foamed plastic sheet and the supporting structure to which it is secured.
A composite panel has been made by adhesively bonding a preformed sheet of foamed plastic to a gypsum wallboard panel. To avoid the problem of nailing such a composite panel to a wall, mechanical clips have been used. Each clip has had flanges extending perpendicularly from lateral edges of a flat web strip to receive and secure adjoining panels edge-face to edge-face, but not necessarily aligning the adjoining panels for flush registry of their exposed surfaces. A flange along one of the lateral edges of the web strip has been nailed to the supporting structure, and prong flanges, extending mutually oppositely from the other lateral edge of the web strip, have penetrated the foamed plastic insulation of the adjoining panels, but not necessarily at the interface of the rigid board and the foamed sheet, and have served to secure them in place without nailing through them. By very careful hand placement of the panels with respect to the foam-penetrating flanges of the clip members, an air space has been formed between the supporting wall and the panels, and the panels have been positioned to obtain a rough degree of flush surface alignment relative to each other. However, proper installation of the panels has been nearly impossible when the supporting structure is a concrete wall, due to deformation of the clip member by the shock of the powder-driven attachment tool which must be used to attach the clip to the concrete wall. In those installations wherein conventional powered tools can be used instead of power driven tools, obtaining proper alignment of the panels has been time consuming and has involved considerable expense for labor.